I must say I am not impressed with Chalmers Johnson's arguent. Blowback is a term that originated in the CIA for the unintended consequence of intervention abroad. Specifically of the form of attacks against the intervening nation's interests. The book is at its essence a critique of the policies of American hegemony.
It does get a good number of things right and raises some important issues. However, it tends to conflates the cases where America was obviously wrong with the tougher calls. Most infuriatingly it invokes some blanket bashing of U.S. support for Taiwan characterizing China's claim as supported by international law and critiquing interference in an ongoing civil war. He isn't calling for a total abandonment of the island, but really, it's a democracy. It's right to continue to be makes this sort of talk. We don't want Taiwan to declare independence because it would probably cause a war, pure and simple. In fairness this is actually a minor point in the book it just really irked me.
Otherwise the book tries to define everything as blowback, expanding the term beyond its practical use. Its introduction is far to light on terrorism and falls prey to sketchy moral equivalency arguments. Moreover, it is primarily a call for U.S. withdrawal from our bases in East Asia; which is a fine point to argue, but one that is only loosely related to the concept of blowback (hence the massive expansion in definition).
Now I shouldn't say the guy has no point or does not acknowledge some legitimate countervailing views, he does both at times. But on the whole, it just is a mediocre policy book that tries to do too much and isn't sufficiently disciplined in its arguments. However, it was timely in its choice of topics, coming out in the year 2000. However, an admittedly good call on an issue to watch in the 21st century does not a good book make. I can't really recommend it. There are doubtless better books out there that make similar arguments; find one of them if you're interested in the topic.